{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T14:43:31Z","timestamp":1783608211774,"version":"3.55.0"},"reference-count":17,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,3,6]],"date-time":"2023-03-06T00:00:00Z","timestamp":1678060800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea (NRF)","doi-asserted-by":"publisher","award":["2022R1F1A1068258"],"award-info":[{"award-number":["2022R1F1A1068258"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Jeonbuk National University","award":["2022R1F1A1068258"],"award-info":[{"award-number":["2022R1F1A1068258"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We propose coating side-polished optical fiber (SPF) with epoxy polymer to form a fiber-optic sensor for cryogenic temperature measuring applications. The thermo-optic effect of the epoxy polymer coating layer enhances the interaction between the SPF evanescent field and surrounding medium, considerably improving the temperature sensitivity and robustness of the sensor head in a very low-temperature environment. In tests, due to the evanescent field\u2013polymer coating interlinkage, transmitted optical intensity variation of 5 dB and an average sensitivity of \u22120.024 dB\/K were obtained in the 90\u2013298 K range.<\/jats:p>","DOI":"10.3390\/s23052850","type":"journal-article","created":{"date-parts":[[2023,3,6]],"date-time":"2023-03-06T03:22:05Z","timestamp":1678072925000},"page":"2850","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Epoxy-Coated Side-Polished Fiber-Optic Temperature Sensor for Cryogenic Conditions"],"prefix":"10.3390","volume":"23","author":[{"given":"Umesh","family":"Sampath","sequence":"first","affiliation":[{"name":"Department of Electronics and Information Engineering, Jeonbuk National University, Jeonju 54896, Republic of Korea"},{"name":"Electronic & Control Group, INZI Controls Co., Ltd., Siheung 15090, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Minho","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Electronics and Information Engineering, Jeonbuk National University, Jeonju 54896, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"18229","DOI":"10.3390\/s150818229","article-title":"In-situ cure monitoring of wind turbine blades by using fiber Bragg grating sensors and Fresnel reflection measurement","volume":"15","author":"Sampath","year":"2015","journal-title":"Sensors"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1016\/j.optlastec.2016.11.021","article-title":"Recent research progress of optical fiber sensors based on D-shaped structure","volume":"90","author":"Ying","year":"2016","journal-title":"Opt. 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Side-Polished Fiber-Optic Temperature Sensor for Cryogenic Conditions. Proceedings of the 26th Conference on Optical Fiber Sensors, Lausanne, Switzerland.","DOI":"10.1364\/OFS.2018.ThE89"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1063\/1.98888","article-title":"Fiber-optic evanescent field absorption sensor","volume":"51","author":"Paul","year":"1987","journal-title":"Appl. Phys. Lett."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"780","DOI":"10.1109\/TIM.2017.2761618","article-title":"Measurement of ultralow level bioethanol concentration for production using evanescent wave based optical fiber sensor","volume":"67","author":"Memon","year":"2017","journal-title":"IEEE Trans. Instrum. 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